Induction Bonding

Induction Bonding has become more widespread as a preferred method of assembly especially in the automotive industry. The method involves accelerating the polymerization of the adhesive by heating the metal parts to be bonded by induction heating equipment. The temperatures required are generally low, in the 150 to 300°C range. This process is now extensively used to manufacture automotive body parts such as doors, hoods, and rear deck lids. Metal to polyester bonds can also be treated by induction heating equipment.

There are essentially two techniques presently being used in industry for applying this technology: 1) Heating the entire perimeter during induction bonding, which involves an inductor that has the same contour as the part being bonded; 2) Heating specific segments, or spot heating, in which case the polymerization zones are heated using small flat magnetic circuit inductors.

With respect to spot bonding, the advantages of this process are:

• The part bonded is not marked. This removes after painting defects and polishing
• Less power consumption
• No corrosion problems associated with welding points
• Adhesive may be combined with sealing strip